Abstract
The fluorotris(triphenylphosphine)copper(I)-bis(methanol) complex-chiral diphosphine system catalyzes the hydrosilylation of several alkyl aryl ketones with moderate to excellent enantioselectivity. An oxygen acceleration effect was observed and led to a practical protocol with low catalyst loading. Optimizations of enantioselectivities (<95%) and catalytic ratio (<0.05 mol%) were obtained with bulky Ar-MeO-BIPHEP ligands.
Key words
asymmetric catalysis - asymmetric hydrosilylation - copper hydride - copper fluoride - oxygen effect
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